Materials Data on U(NiAs)2 by Materials Project
U(NiAs)2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. U3+ is bonded in a 8-coordinate geometry to eight As3- atoms. There are four shorter (3.12 Å) and four longer (3.13 Å) U–As bond lengths. There are two inequivalent Ni+1.50+ sites. In the first Ni+1.50+ site, Ni+1.50+ is bonded to four equivalent As3- atoms to form a mixture of edge and corner-sharing NiAs4 tetrahedra. All Ni–As bond lengths are 2.41 Å. In the second Ni+1.50+ site, Ni+1.50+ is bonded in a 5-coordinate geometry to five As3- atoms. There are one shorter (2.30 Å) and four longer (2.35 Å) Ni–As bond lengths. There are two inequivalent As3- sites. In the first As3- site, As3- is bonded in a 4-coordinate geometry to four equivalent U3+ and four equivalent Ni+1.50+ atoms. In the second As3- site, As3- is bonded in a 5-coordinate geometry to four equivalent U3+ and five Ni+1.50+ atoms.